In her book, exclusively obtained by Life & Style, Brandi writes about the day she found out about Eddie’s affair. “I’m not entirely sure how I ended up on the floor of my closet sobbing…a teary-eyed Eddie found me lying there minutes later, and without saying so much as a word, he started kissing me all over…he pulled off my workout pants and we started having sex right there,” she recalls. “He swore up and down my body that it wasn’t true…that it was completely innocent. In that moment, it was easier to believe him, because I just couldn’t stand the thought of being without him.”

But the 40-year-old, who has two sons, Mason, 9, and Jake, 5, with Eddie, knew there was something going on between her ex and LeAnn after the two met on the set of the TV movie Northern Lights in fall 2008.

“LeAnn had ‘accidentally’ smeared some cake frosting on her top (she was still a bigger girl and completely flat-chested at the time) and asked my husband, not realizing that I was standing behind the both of them, if he wanted lick it off her,” she recalls in the book. “This woman asked my husband if he wanted to eat the frosting mess she’d dropped on her nonexistent chest? … He hadn’t realized I was there, either, and he laughed with hungry eyes at the suggestion.”

Even after Brandi and Eddie split, the reality star says her ex promised “he would never marry LeAnn, but that was just one of the countless lies he told me.”

For Brandi, her life curtailed, and she found herself homeless, without a dime or credit to her name following their divorce. “I was a jobless, homeless, mother of two living out of her $1,200-a-month SUV and couch-surfing from one hospitable friend to the next,” she explains. “After my divorce — even with the help of Lexapro — I fell into a bit of a tailspin [and an eventual DUI arrest]. White wine became my constant shoulder to lean on."

Of course, she got her revenge — by way of vaginal rejuvenation. “This pretty intense surgery had an even more intense price tag: $12,000,” Brandi reveals. "A brand-new vagina would be an Eddie-free vagina…. I decided that since Eddie had ruined my vagina for me, he could pay for a new one. I gave [the doctor's office] Eddie's credit card number.”

Looking back, she appreciates everything she’s been through. “I would like to thank my ex-husband, Edward Cibrian, for giving me all the material I could ever need to write this book and for helping me discover the strong independent woman inside of me,” she writes.